Injection device



March 9, 1954' G. N. HEINfJR INJECTION DEVICE Filed Aug. 4, 1951 21" Z6 Z0 24 3 22M a 35 i: In!! "Il j 12-15 j? 5 f- Z ZZ f6 34 M17 il l I III Q: :n l n j 12 g 1 6 wl zl g 5 y/, 6

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4 14 i j? l0 11 6 Patented Mar. 9, 1954 UNITED STATES PATENT CFFICE INJECTION DEVICE George N. Hein, Jr., San Carlos, Calif.

Application August 4, 1951, Serial No. 240,411

(Cl. 12S-173) 2 Claims.

This invention relates to a structurally and functionally improved injection device. While the present teachings may be generally employed in connection with the hypodermic injection ci medicaments, the preferred embodiment of the apparatus will be one in which medicament is discharged from the apparatus under pressures and in a suiiiciently fine stream such that it will penetrate the epidermis without it being necessary to employ a skin-piercing needle.

It is an object of the invention to furnish a unit of this type which will primarily be intended for self-injection to be used periodically by diabetics and in similar cases rather than being intended for substantially continuous use by a physician.

A further object is that of providing an apparatus which will be of extremely simple and economical design and which may be operated by an unskilled person to satisfactorily inject medicaments to the desired depth.

A still further object is that of designing an injection device the stroke of which may be powered in accordance with the needs of the patient and the instructions of the physician; the variations in this power stroke being capable of ready achievement.

With these and other objects in mind reference is had to the attached sheet of drawings illustrating one practical embodiment of the invention and in which:

Fig. 1 is a plan View of the device;

Fig. 2 is a side elevation thereof;

Fig. 3 is a sectional side View taken along the line 3-3 and in the direction of the arrows as indicated in Fig. 1 and Fig. 4 is a transverse sectional view taken along the line 4 4 and in the direction of the arrows as indicated in Fig. 3.

In these views the numeral 5 indicates the body of the device which is formed with a bore within which a rod 6 may reciprocate to function as a plunger. For the purpose of manipulating the body a handle may be aflixed thereto. Conveniently this part is skeletonized. It may take the form of a strap 7, the forward edge of which is formed with undulations to receive the ngers of the user. A latch structure is furnished which is operated by means of a trigger 8 pivotally supported as at 9 preferably by an integral portion of the frame of the unit. Regardless of the design congurations and general appearance of the unit it is thus apparent that an apparatus is provided which may readily be grasped (similarly to a pistol) by the hand of the user who may employ one of his lingers to shift trigger 8.

Adjacent its forward end body 5 is provided with a medicament chamber. The latter may take one of numerous different forms. Conveniently and as shown it will embrace a member removable from -body 5 which member may readily be sterilized and filled with the desired quantity of medicament. As such the member enclosing the medicament may embrace a body I0 which is slightly flared in an outward direction and includes a base portion from which a stem II extends in the direction of the plunger 6 and within the bore of body 5. Member I0, as well as stem I I may be formed of rubber or suitable equivalent material. As indicated in dotted lines in Fig. 3, the base of the cup member I0 may, under projection of stem II, be moved towards the outer end of the member. Under these circumstances, the side walls of that member will invert upon themselves. This inverting will continue as the parts are projected until the stem II has its forward portion lying adjacent the outer open end of the cup member I0. Under these circumstances the side walls of that member will have folded upon themselves and will occupy the space between the enlarged bore portion of body 5 (providing the medicament chamber) and the side wall of stem I I.

Having in mind that the present apparatus is preferably of the velocity injection type, the instant illustration includes a suitable nozzle as part of the assembly rather than a skin-piercing hollow needle. Thus a nozzle has been indicated at l2 and the inner face of which conveniently conforms to the outer end of stem II. This nozzle adjacent its outer or discharge end may present an oriiice or sufficiently restricted diameter that a medicament stream of adequate lineness may be expelled therefrom. Ordinarily the most restricted part of the nozzle bore will not be below .004" nor Will it customarily exceed .015". The base of nozzle I2 may be in the form of a radially extending iiange which couples with and overlaps a flange adjacent the outer end of cup member I 0. These flanges have been respectively indicated at I3 and I4. A loading cap I5 may be formed with a central aperture of a diameter adequate to accommodate the nozzle tip I2. 'Ihe loading cap is conveniently secured in position by screw threads or any other form of quick detachable coupling by means of which it may readily be mounted upon or dismounted from body 5. In any event it will be appreciated with a structure such as this that the loading cap will prevent any accidental detachment of the cup member from the nozzle or a. displacement of 3 either of these units from proper association with body 5. At the same time when the loading cap is dismounted, then the nozzle and cup member may readily be withdrawn and detached from each other. Thereupon, if necessary, one or both may be sterilized and cup member I may be lled with a proper solution.

A strain receiving member conveniently embracing a pair of arms I6 is provided with a hub portion I 1 slidably mounted upon the reduced rear end of plunger rod 6. A cap I8 may have threaded engagement with threads I 9 at the rear end of that rod and function as a stop to prevent rearward displacement of member I6; A second stop in the form of a collar bears against a shoulder forming a part of rod 6 in advance of member I6. A spring 2| of proper value may be interposed between collar 20 and the base of this member. Preferably and as shown the forward end of that member includes a tubular part 22 which houses the spring and slightly overlaps collar 20. The forward edge of tubular portion 22 may be reduced so that as it traverses the surface of collar 20 it will visually register with one of a series of indicating marks 23. Conveniently its reduced surface may also be provided with a cooperating indicia mark 24.

Fixed with respect to body 5 and preferably integral therewith are forwardly extending bracket arms 25 corresponding to the arms I6 of the first described strain member. An elastic unit 26 may have its ends disposed between arms 25 with its body extending between those arms and arms I6 through a number of turns. The elastic member 26 may be in the form of a shock cord or tube of rubberor similar material. Likewise it might be in the form of a spring. However it is preferred that a. cord or tubing be employed so that there will be no danger of the fingers or skin of the operator being injured as he operates the device. As will be understood if this elastic member may, without difficulty, be placed under a tension of ten pounds then for each vcourse of `that member between arms 25 and I6 an additional .pull value of ten pounds will be brought into being. Assuming for example that twelve courses are involved then, under these circumstances, a total pull of 120 lbs. would exist. 'I'he forwarder inner end of member 26 may .conveniently be disposed at a point beyond arm I6 by simply being passed under one of the courses of its body. So disposed it will be locked in position against accidental displacement.

Witha view to providing a suitable latch structure actuated, for example, by the Ytrigger `8 one of a number of different arrangements may be employed. However, it is preferred that this latch structure be in the nature of a 'friction detent. To this -end the inner portion lof trigger 8 may terminate in a cam 21. This cam engages and serves to shift a displacement pin 28 slidably mounted Aby body 5. The pin extends into a pocket or recess within which there is received a body of rubber v29 or equivalent material. This in turn may thrust against a pressure saddle or block 3l. A screw 30 may have threadedengagement with a bore extending through to this vrecess so as to vary the pressure exerted against the resilent Ybody '29. A safety pin V.'-iI' may be furnished which extends transversely of the triggermounting and is provided with a knob V32. By having this pin notched or formed with a recess 'it may in one position Aserve to arrest my .movsmsnefiihe Wieser 8- When. adjusted,

to another position it will allow that trigger to be pivoted around the pin or mounting 9.

A displacement of the plunger from body 5 is conveniently prevented by employing a bolt 33, the reduced end of which rides against a fiat face 34 formed on plunger 6. This bolt is mounted by body 5. Additionally as shown plunger or piston 6 may be provided with a series of indicating marks 35 intervening the rear end of body 5 and collar 20. According to the capacity of the assembly these indicating marks may cover different ranges. Ordinarily it may be assumed that the apparatus would have a capacity of 1 cc. Under these circumstances the indicia at 35 may conveniently be graduated through onequarter (1A), one-half (1/2), three-quarter (3A), and 1 cc. marks.

Assuming that the apparatus is to be employed for lan injection, then the medicament chamber will be loaded for example in the manner heretofore described and so that stem II is disposed within the bore of body 5 and abuts plunger 6. The latter, under these circumstances, will be retracted. The elastic strand 26 will not be in place. The operator will now shift pin 3| so that trigger 8 may be brought to the elevated position shown. Under these circumstances the periphery of cam 21 will project displacement pin 28. Accordingly the latter will extend into the body of rubber or equivalent material 29 to a maximum extent and thus displace the upper surface of that body. Therefore saddle block 3I will be forced upwardly into rm engagement with plunger 6. Under these circumstances that plunger' or piston will be restrained against any movements with respect to body 5. As afore brought out other forms of latch mechanisms could be employed. These would produce the same functional results.

The user will now employ the elastic strand 26 the forward end of which will be conveniently anchored as afore described and the body of which will be disposed throughout a series of convolutions to provide the desired number of courses. The strength of the aggregate pull exerted by the elastic member may be gauged by observing the indicia at 23-24. With a suffi' ciently strong spring,r 2I in place the operator will have no difliculty in determining the value of the tension which has been established. Of course that tension may also be approximated according to the strain exerted on member 26 and the number of turns ,of the latter.

In any event if the instrument is now dis-v posed with the tip of the nozzle in contact with the surface of the skin overlying the area to be injected then with .pin 3|' properly shifted, trigger 8 may be rotated. With lsuch rotation displacement pin 26 will retract. This will relieve the thrust on saddle block SI allowing plunger' Yto project. With such projection stem -II will be vthrust towards the outer end of vthe apparatus and cup I will invert upon itself; this operation continuing until all medicament has been ejected from nozzle I2. The expulsion of the solution will occur under pressures and velocities such that with the stream being of the desired neness it will penetrate the epidermis. Thereupon loading cap I5 may be dismounted, the parts may be cleaned and refilled and the entire operation repeated.

In the event it is found desirable to do so the compression on block 3| may be relieved -by retracting screw 30. Similarly by projecting this screw 4,the internal pressures on this block and in turn on the saddle member 3| may be increased, Therefore Wear may be compensated for. If only a fractional dosage is desired then the medicament chamber Will be lled accordingly and piunger 6 Will be retracted to less than its full extent as evidenced by the indicia 35. The operation will otherwise be identical with that as heretofore described.

Thus, among others, the several objects of the invention as specifically afore noted are achieved. Obviously numerous changes in construction and rearrangement of the parts might be resorted to Without departing from the spirit of the invention as dened by the claims.

I claim:

l. A velocity injection device including in combination a body providing an ampule chamber, a plunger slidably carried by said body and projectible to expel medicament from said chamber', supporting means carried by said plunger and body respectively to receive between them an elastic tensioning element, a body of rubber carried by said body and yieldingly acting on said plunger to restrain movements of the 6 latter and means for displacing a portion of said body.

2. A velocity injection device including in Acombination a body providing an ampule chamber, a plunger slidably carried by said body and projectible to expel medicament from said chamber, supporting means carried by said plunger and body respectively to receive between them an elastic tensioning element, a body of rubber carried by said body and yieldingly acting on said plunger to restrain movements of the latter and cam means in the form of a trigger movably carried by said body, said cam means acting upon said rubber body to displace the latter.

GEORGE N. HEIN, JR.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 163,673 Martin May 25, 1875 508,152 Stauth et a1 Nov. 7, 1893 1,290,898 Burlin Jan. 14, 1919 2,380,534 Lockhart July 31, 1945 

